Add simulation generic device/value support

This allows high-level library classes to implement enhanced simulation
support even if no low-level corresponding simulation library exists, and
avoids the need for bit-banging complex interfaces like SPI or CAN.

hal/src/main/native/cpp/jni/SimDeviceJNI.cpp

@@ -0,0 +1,168 @@
+/*----------------------------------------------------------------------------*/
+/* Copyright (c) 2019 FIRST. All Rights Reserved.                             */
+/* Open Source Software - may be modified and shared by FRC teams. The code   */
+/* must be accompanied by the FIRST BSD license file in the root directory of */
+/* the project.                                                               */
+/*----------------------------------------------------------------------------*/
+
+#include <jni.h>
+
+#include <wpi/jni_util.h>
+
+#include "HALUtil.h"
+#include "edu_wpi_first_hal_SimDeviceJNI.h"
+#include "hal/SimDevice.h"
+
+using namespace wpi::java;
+
+static HAL_Value ValueFromJava(jint type, jlong value1, jdouble value2) {
+  HAL_Value value;
+  value.type = static_cast<HAL_Type>(type);
+  switch (value.type) {
+    case HAL_BOOLEAN:
+      value.data.v_boolean = value1;
+      break;
+    case HAL_DOUBLE:
+      value.data.v_double = value2;
+      break;
+    case HAL_ENUM:
+      value.data.v_enum = value1;
+      break;
+    case HAL_INT:
+      value.data.v_int = value1;
+      break;
+    case HAL_LONG:
+      value.data.v_long = value1;
+      break;
+    default:
+      break;
+  }
+  return value;
+}
+
+extern "C" {
+
+/*
+ * Class:     edu_wpi_first_hal_SimDeviceJNI
+ * Method:    createSimDevice
+ * Signature: (Ljava/lang/String;)I
+ */
+JNIEXPORT jint JNICALL
+Java_edu_wpi_first_hal_SimDeviceJNI_createSimDevice
+  (JNIEnv* env, jclass, jstring name)
+{
+  return HAL_CreateSimDevice(JStringRef{env, name}.c_str());
+}
+
+/*
+ * Class:     edu_wpi_first_hal_SimDeviceJNI
+ * Method:    freeSimDevice
+ * Signature: (I)V
+ */
+JNIEXPORT void JNICALL
+Java_edu_wpi_first_hal_SimDeviceJNI_freeSimDevice
+  (JNIEnv*, jclass, jint handle)
+{
+  HAL_FreeSimDevice(handle);
+}
+
+/*
+ * Class:     edu_wpi_first_hal_SimDeviceJNI
+ * Method:    createSimValueNative
+ * Signature: (ILjava/lang/String;ZIJD)I
+ */
+JNIEXPORT jint JNICALL
+Java_edu_wpi_first_hal_SimDeviceJNI_createSimValueNative
+  (JNIEnv* env, jclass, jint device, jstring name, jboolean readonly, jint type,
+   jlong value1, jdouble value2)
+{
+  return HAL_CreateSimValue(device, JStringRef{env, name}.c_str(), readonly,
+                            ValueFromJava(type, value1, value2));
+}
+
+/*
+ * Class:     edu_wpi_first_hal_SimDeviceJNI
+ * Method:    createSimValueEnum
+ * Signature: (ILjava/lang/String;Z[Ljava/lang/Object;I)I
+ */
+JNIEXPORT jint JNICALL
+Java_edu_wpi_first_hal_SimDeviceJNI_createSimValueEnum
+  (JNIEnv* env, jclass, jint device, jstring name, jboolean readonly,
+   jobjectArray options, jint initialValue)
+{
+  size_t len = env->GetArrayLength(options);
+  std::vector<std::string> arr;
+  arr.reserve(len);
+  for (size_t i = 0; i < len; ++i) {
+    JLocal<jstring> elem{
+        env, static_cast<jstring>(env->GetObjectArrayElement(options, i))};
+    if (!elem) return 0;
+    arr.push_back(JStringRef{env, elem}.str());
+  }
+  wpi::SmallVector<const char*, 8> carr;
+  for (auto&& val : arr) carr.push_back(val.c_str());
+  return HAL_CreateSimValueEnum(device, JStringRef{env, name}.c_str(), readonly,
+                                len, carr.data(), initialValue);
+}
+
+/*
+ * Class:     edu_wpi_first_hal_SimDeviceJNI
+ * Method:    getSimValue
+ * Signature: (I)Ljava/lang/Object;
+ */
+JNIEXPORT jobject JNICALL
+Java_edu_wpi_first_hal_SimDeviceJNI_getSimValue
+  (JNIEnv* env, jclass, jint handle)
+{
+  return frc::CreateHALValue(env, HAL_GetSimValue(handle));
+}
+
+/*
+ * Class:     edu_wpi_first_hal_SimDeviceJNI
+ * Method:    getSimValueDouble
+ * Signature: (I)D
+ */
+JNIEXPORT jdouble JNICALL
+Java_edu_wpi_first_hal_SimDeviceJNI_getSimValueDouble
+  (JNIEnv*, jclass, jint handle)
+{
+  return HAL_GetSimValueDouble(handle);
+}
+
+/*
+ * Class:     edu_wpi_first_hal_SimDeviceJNI
+ * Method:    getSimValueEnum
+ * Signature: (I)I
+ */
+JNIEXPORT jint JNICALL
+Java_edu_wpi_first_hal_SimDeviceJNI_getSimValueEnum
+  (JNIEnv*, jclass, jint handle)
+{
+  return HAL_GetSimValueEnum(handle);
+}
+
+/*
+ * Class:     edu_wpi_first_hal_SimDeviceJNI
+ * Method:    getSimValueBoolean
+ * Signature: (I)Z
+ */
+JNIEXPORT jboolean JNICALL
+Java_edu_wpi_first_hal_SimDeviceJNI_getSimValueBoolean
+  (JNIEnv*, jclass, jint handle)
+{
+  return HAL_GetSimValueBoolean(handle);
+}
+
+/*
+ * Class:     edu_wpi_first_hal_SimDeviceJNI
+ * Method:    setSimValueNative
+ * Signature: (IIJD)V
+ */
+JNIEXPORT void JNICALL
+Java_edu_wpi_first_hal_SimDeviceJNI_setSimValueNative
+  (JNIEnv*, jclass, jint handle, jint type, jlong value1, jdouble value2)
+{
+  HAL_SetSimValue(handle, ValueFromJava(type, value1, value2));
+}
+
+}  // extern "C"